Over the past decade, the issue of climate change has risen rapidly to an important position on international scientific and political agendas. A number of key events in this process may be identified, beginning with the 1988 Conference on "The Changing Atmosphere" (World Meteorological Organization 1989), and the consequent establishment of the Intergovernmental Panel on Climate Change (IPCC). The three Working Groups of the IPCC presented their first reports (Houghton et al. 1990; Tegart et al. 1990; IPCC Working Group III 1990) to the Second World Climate Conference in 1990 (Jaeger and Ferguson 1991), which provided a major impetus to the formulation of a Framework Convention on Climate Change. This was signed by the heads of state of most of the world's nations at the 1992 UN Conference on Environment and Development. Yet, although mountains occupy a considerable part of the world's land surface and are directly or indirectly vital for a significant proportion of the global population, little explicit attention has been given to the possible implications of climate change for mountain ecosystems. Only one international meeting, held in 1992 in Davos, Switzerland, has been entirely devoted to this topic (ProClim 1992).
For those who make decisions concerning the future of mountain regions, recognition of the likelihood of rapid climate change leads to some of the greatest uncertainties they are likely to face. The purpose of this chapter is to outline the complexities and implications connected with climate change and its potential results for mountain areas. This chapter considers, first, climate change and climates; second, potential changes in mountain ecosystems-particularly their vegetation-resulting from climate change and, third, methods for assessing these changes. It concludes with a discussion of some of the long-term implications to be considered by those responsible for managing mountain protected areas.